Structures and luminescent properties of four compounds based on binuclear metal-terpyridine building blocks

<p>Four new coordination polymers, [Cd(3-TPTP)Cl]<sub>2</sub> (3-HTPTP = 4′-(3-tetrazolylphenyl)2,2′:6′2′′-terpyridine, <b>1</b>), <b>{</b>[Cd(3-TPTP)(<i>p</i>BDC)<sub>0.5</sub>]∙4H<sub>2</sub>O}<sub>n</sub> (<i>p</i>H<sub>2</sub>BDC = 1,4-benzenedicarboxylic acid, <b>2</b>), {[Mn(3-TPTP)(<i>m</i>BDC)<sub>0.5</sub>]∙5H<sub>2</sub>O}<sub>n</sub> (<i>m</i>H<sub>2</sub>BDC = 1,3-benzenedicarboxylic acid, <b>3</b>), and [Pb(3-TPTP)(H<sub>2</sub>O)<sub>2</sub>]∙OH (<b>4</b>), were obtained. Compounds <b>1</b>–<b>3</b> are composed of binuclear [M<sub>2</sub>(3-TPTP)<sub>2</sub>] ring as building unit. In <b>1</b>, the binuclear rings pack into a 3-D supramolecular framework via various hydrogen bonds. In <b>2</b> and <b>3</b>, the binuclear rings are connected by <i>m</i>BDC<sup>2−</sup> and <i>p</i>BDC<sup>2−</sup>, respectively, resulting in two types of 1-D chains. In <b>4</b>, the mononuclear [Pb(3-TPTP)] units are connected by Pb⋯N weak interactions, giving a chiral 1-D coordination chain, which is further connected by O–H⋯N interaction to form a chiral 3-D supramolecular framework. The phase purity of <b>1</b>–<b>4</b> and luminescence properties of <b>1</b>, <b>2</b>, and <b>4</b> were also investigated.</p>